package com.sky.service.impl;

import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.List;

@Service
public class ShoppingCartServiceImpl implements ShoppingCartService {

    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private DishMapper dishMapper;
    @Autowired
    private SetmealMapper setmealMapper;

//    添加购物车
    @Override
    public void addShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        //1.判断当前加入到购物车中的商品是否已经存在了
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        Long userId = BaseContext.getCurrentId();
        shoppingCart.setUserId(userId);

        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        //2.如果已经存在了，只需要将数最加1   update
        if (list!=null && list.size()>0){
            ShoppingCart cart = list.get(0);
            cart.setNumber(cart.getNumber()+1);  //update shopping_cart set number=? where id=?
            shoppingCartMapper.updateNumberById(cart);
        }else {
            //如果不存在、需要插入一条购物车数据
//            判断添加到购物车的是菜品还是套餐
            Long dishId = shoppingCartDTO.getDishId();
            if (dishId!=null){
//                本次添加到购物车的是菜品
                Dish dish = dishMapper.getById(dishId);
                shoppingCart.setName(dish.getName());
                shoppingCart.setImage(dish.getImage());
                shoppingCart.setAmount(dish.getPrice());

            }else {
//                本次添加到购物车的是套餐
                Setmeal setmeal = setmealMapper.getById(shoppingCartDTO.getSetmealId());
                shoppingCart.setName(setmeal.getName());
                shoppingCart.setImage(setmeal.getImage());
                shoppingCart.setAmount(setmeal.getPrice());
            }
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartMapper.insert(shoppingCart);
        }
    }

//    查看购物车
    @Override
    public List<ShoppingCart> showShoppingCart() {
//        获取当前登录用户id
        Long userId = BaseContext.getCurrentId();

        ShoppingCart shoppingCart = ShoppingCart.builder().userId(userId).build();
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        return list;
    }

//    清空购物车
    @Override
    public void clanShoppingCart() {
        Long userId = BaseContext.getCurrentId();
        shoppingCartMapper.deleteByUserId(userId);
    }

//    删除购物车中一个商品
    @Override
    public void subShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        shoppingCart.setUserId(userId);

        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        if (list!=null && list.size()>0){
            //只有一条数据，list.get(0)就可以取到第一条并且仅有一条数据
            shoppingCart= list.get(0);
//            如果数量为1，删除这条数据
            if (shoppingCart.getNumber()==1){
                shoppingCartMapper.deleteById(shoppingCart.getId());
            }else {
//                如果数量大于1，则number-1
                shoppingCart.setNumber(shoppingCart.getNumber()-1);
                shoppingCartMapper.updateNumberById(shoppingCart);
            }
        }
    }
}
